<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .picture-list img{
            width:320px;
            height:160px;
        }
        .big-picture img{
            width:640px;
            height:320px;
        }
        .big-picture{
            position: absolute;
        }
    </style>
</head>
<body>
    <div class="picture-list">
        <img src="images/1.png" alt="">
        <img src="images/2.png" alt="">
        <img src="images/3.png" alt="">
    </div>
    <div class="big-picture"></div>
    <script>
        let imgList = document.querySelectorAll('.picture-list img');
        let bigPictrue = document.querySelector('.big-picture')
        let picList = document.querySelector('.picture-list')
        for(let i in imgList){
            imgList[i].onmouseenter = function(){
                // console.log(this.src);
                bigPictrue.innerHTML = `<img src='${this.src}'>`
            }
            imgList[i].onmouseleave = function(){
                bigPictrue.innerHTML = ''
            }
        }
        picList.onmousemove = function(e){
            let x = e.clientX;
            let y = e.clientY;
            bigPictrue.style.top = y + 10 + "px";
            bigPictrue.style.left = x + 10 + "px";

        }
    </script>
</body>
</html>